Cement augmentation of humeral head screws reduces early implant-related complications after locked plating of proximal humeral fractures

Proximal humerus fracture and acromioclavicular joint dislocation

Proximal humerus fractures and injuries to the acromioclavicular joint are among the most common traumatic diseases of the upper extremity. Fractures of the proximal humerus occur most frequently in older people and are an indicator fracture of osteoporosis. While a large proportion of only slightly displaced fractures can be treated non-operatively, more complex fractures require surgical treatment. The choice of optimal treatment and the decision between joint-preserving surgery by means of osteosynthesis or endoprosthetic treatment is often a difficult decision in which both fracture morphology factors and individual factors should be taken into account. If endoprosthetic treatment is indicated, satisfactory long-term functional and clinical results have been achieved with a reverse shoulder arthroplasty. Injuries to the acromioclavicular joint occur primarily in young, athletic individuals. The common classification according to Rockwood divides the injury into 6 degrees of severity depending on the dislocation. This classification forms the basis for the decision on non-operative or surgical treatment. The indication for surgical treatment for higher-grade injuries is the subject of controversial debate in the latest literature. In chronic injuries, an autologous tendon transplant is also performed. Whereas in the past, treatment was often carried out using a hook plate, which was associated with complications, the gold standard today is minimally invasive treatment using Endobutton systems. This review provides an overview of the two injury patterns and discusses the various treatment options.

Cement-augmented locked plate fixation proximal humerus fractures in elderly patient: a systematic review and meta-analysis

BACKGROUND

This systemic review and meta-analysis aimed to evaluate the clinical outcomes of proximal humeral fracture in elderly patient fixation using locked plate with or without cement augmentation.

METHODS

The databases of PubMed, Embase, and Cochrane Library were searched in August 2023 for literature comparing the clinical outcomes of patients with PHFs treated with locked plate alone and locked plate augmented with cement. Data describing study design; level of evidence; inclusion criteria; demographic information; final follow-up; revision rate; implant failure rate; avascular necrosis rate; total complication rate; constant score; and disability of arm, shoulder, and hand (DASH) score were collected.

RESULTS

Eight studies (one randomized-controlled trial and seven observational studies), involving 664 patients, were identified. Compared with locked plates alone, using cement-augmented locked plates reduced the implant failure rate (odds ratio (OR) = 0.19; 95% confidence interval (CI) 0.10-0.39; P < 0.0001) and total complication rate (OR = 0.45; 95% CI 0.29-0.69; P = 0.0002) and improved DASH scores (mean difference (MD) = 2.99; 95% CI 1.00-4.98; P = 0.003). However, there was no significant difference in clinical outcomes, including revision rate, avascular necrosis rate, and constant score.

CONCLUSION

In this review and meta-analysis, fixation of the PHFs in elderly patients using locked plates with or without cement augmentation has no significant difference in revision rate, but the implant failure and total complication rates may be lesser on using the cement-augmented locked plate for fixation than on using a locked plate alone. Good results are expected for most patients treated with this technique.

TRIAL REGISTRATION

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)21 guidelines were followed to conduct this systematic review and meta-analysis and was registered as a protocol in PROSPERO (CRD42022318798).

Cement augmentation for proximal humerus fractures: a meta-analysis of randomized trials and observational studies

INTRODUCTION

It is unclear if elderly patients treated with plate osteosynthesis for proximal humerus fractures benefit from cement augmentation. This meta-analysis aims to compare cement augmentation to no augmentation regarding healing, complications, and functional results.

METHODS

PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched for randomized clinical trials and observational studies. Effect estimates were pooled across studies using random effects models. The primary outcome is overall complication rate. Stratified analyses were performed for types of complication (implant-related or systemic). Secondary outcomes include re-interventions, hospital stay, operation time, functional scores, and general quality of life.

RESULTS

Five observational studies and one randomized controlled trial with a total of 541 patients were included. The overall complication rate was significantly lower in the augmented group (15.6% versus 25.4%, OR 0.54 (95%CI 0.33-0.87)). This was caused by a reduction of implant-related complications (10.4% vs. 19.9%, OR 0.49 (95%CI 0.28, 0.88)). No difference in humeral head necrosis was found. Data on re-intervention, hospital stay, and operation time was limited but did not show significant differences. No impact on functional scores and general quality of life was detected.

CONCLUSION

This meta-analysis shows that cement augmentation may reduce overall complications, mainly by preventing implant-related complications. No difference was detected regarding need for re-intervention, functional scores, general quality of life, and hospital stay. This is the first meta-analysis on this topic. It remains to be seen whether conclusions will hold when more and better-quality data becomes available.

[Augmentation techniques for the treatment of osteoporosis-associated fractures of the extremities]

The current demographic development is leading to an increasing number of cases of osteoporosis-related fractures. Affected individuals are typically part of a vulnerable, predominantly geriatric patient group with limited physical resources. Additionally, the pathophysiological characteristics of osteoporotic bones with reduced bone quality and quantity, pose a significant challenge to the osteosynthesis techniques used. Achieving rapid postoperative mobilization and stable weight-bearing osteosynthesis to prevent postoperative medical complications are the main goals of the surgical management. In recent years augmentation techniques have gained in importance in the treatment of osteoporosis-related fractures by significantly enhancing the stability of osteosyntheses and reducing mechanical complication rates. The main options available are polymethyl methacrylate (PMMA) augmentation and various bioresorbable bone substitute materials with different properties. Implant augmentations can be applied at various locations in the extremity bones and standardized procedures are now available, such as for the proximal humerus and femur. When used correctly, low complication rates and promising clinical outcomes are observed. This article aims to provide an overview of available techniques and applications based on the current literature. Guidelines and substantial scientific evidence are still limited.

Plate Fixation of Proximal Humerus Fractures: How to Get It Right and Future Directions for Improvement

PURPOSE OF REVIEW

Open reduction and internal fixation with locking plates (ORIF-LP) has been used for decades for the surgical management of proximal humerus fractures. Despite good outcomes have been widely published in the literature, unacceptably high rates of complications (up to 40%), many of them yielding poor outcomes and requiring reoperation (up to 25%), have also been reported, especially in elderly patients. Most common complications are related to implant failure, with intra-articular screw penetration as the most frequent and devastating.

RECENT FINDINGS

Advances in patient selection and surgical technique, and implementation of bone or cement augmentation, have been developed to hopefully decrease complication rates. Mayo-FJD Classification offers prognostic information that can aid in the decision-making process for proximal humeral fractures. Displaced valgus impacted fractures seem to be associated with well over a 10% rate of avascular necrosis after ORIF-LP. A principle-based and stepwise surgical technique combining anatomic reduction and a short screw configuration can provide good outcome in most patients, even the elderly, decreasing implant failures to less than 10%. Acrylic cement augmentation has the potential to further decrease implant failure rate to 1%. Reoperation rates are higher partly due to the need to remove hardware for painful subacromial conflict. However, no studies to date definitively demonstrated the superiority of ORIF-LP compared to non-operative treatment, intramedullary nailing, or reverse shoulder arthroplasty. ORIF-LP can provide good results for the surgical management of displaced proximal humerus fractures even in elderly patients provided adequate patient selection and a principle based and stepwise surgical technique, supplemented with bone graft or acrylic cement when needed. Poor outcomes and high complication and reoperation rates should be expected when these recommendations are not followed.

Double Plating for Complex Proximal Humeral Fractures: Clinical and Radiological Outcomes

Double plating for proximal humeral fractures (PHF) is an option to increase the primary fixation stability. Clinical data is missing for assessment of clinical and radiological outcome, as well as complications. We retrospectively examined 35 patients with unilateral PHF, who were treated with double plating for PHF between 2013 and 2019. The mean age was 59.5 ± 12 years and the leading fracture type was a varus dislocation (Resch type IV in 55.3%). A head-split was present in 22.9% of the cases. The primary outcome measurement was the radiological neck shaft angle (NSA). The radiological follow-up was 21 ± 16.6 months and the NSA did not differ between the intraoperative and follow-up time point (131.5 ± 6.9° vs. 136.6 ± 13.7°; p = 0.267). The clinical follow-up was 29.5 ± 15.3 months. The Constant-score was 78.5 ± 17 points, the simple-shoulder-test (SST) was 9.3 ± 3.2 points and the subjective shoulder value (SSV) was 78.8 ± 19.5%. The over-all complication rate was 31.4%, and without stiffness 14.3%. An avascular necrosis occurred in two patients (5.7%). In conclusion, this study shows good radiological and functional outcomes after double plating of highly complex proximal humeral fractures, while the complication rate is comparable to the literature. Double plating is a viable option especially for younger patients with complex fractures as a potential alternative to fracture arthroplasty.

Role of Fibular Allograft in Proximal Humerus Fractures: A Systematic Review

OBJECTIVES

To analyze the outcomes and complication rates of fibular allografts (FA) as an augmentation technique for proximal humeral fractures and determine their appropriate indications.

DATA SOURCES

English- and Spanish-language articles in PubMed, MEDLINE, Embase, Web of Science (Core Collection), and Google Scholar databases were systematically reviewed with the Preferred Reporting Items for Systematic Reviews guidelines on April 10, 2020.

STUDY SELECTION

Studies of patients with proximal humeral fractures treated primarily with FA and locking compression plates and with a minimum follow-up of 6 months were included, and presenting results with standardized clinical scales, radiological values, and operative complications.

DATA EXTRACTION

Two authors independently extracted data from the selected studies with a standardized data collection form. Subsequently, each extracted data set was consolidated on the agreement of authors.

DATA SYNTHESIS

From the initial screening of 361 articles, 5 case series and 6 retrospective cohort studies were included. A meta-analysis was not performed.

CONCLUSIONS

FA improved the clinical and radiological results, thereby reducing complications. The optimal indication for this procedure may be a 4-part fracture with medial column disruption in younger adults.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

[Augmentation in the treatment of proximal humeral and femoral fractures]

BACKGROUND

Proximal humeral and trochanteric femoral fractures in older patients are typically caused by low-energy trauma and are therefore often associated with osteoporosis. The treatment of such fragility fractures can be difficult as implant purchase is reduced in osteoporotic bone. By augmenting the fixation with cement the contact surface between implant and bone can be increased, which improves the stability of the osteosynthesis.

OBJECTIVE

This article describes the operative technique for the augmentation of trochanteric femoral fractures treated with the Trochanteric Fixation Nail-Advanced (TFNA, DePuy Synthes, Oberdorf BL, Switzerland) and proximal humeral fractures stabilized with a PHILOS plate (DePuy Synthes). Furthermore, the evidence for the augmentation of these two fracture types is elucidated.

RESULTS

Biomechanical studies could show an improved stability of the osteosynthesis after successful augmentation for both fracture types. The current evidence also indicates a clinical reduction of fixation failure. Whether the augmentation has an influence on the functional result could so far not yet clearly be proven.

CONCLUSION

Augmentation seems to be a safe and valuable addition to available treatment options especially for patients with fragility fractures.

Age-Independent Clinical Outcome in Proximal Humeral Fractures: 2-Year Results Using the Example of a Precontoured Locking Plate

INTRODUCTION

The optimal treatment strategy for the proximal humeral fracture (PHF) remains controversial. The debate is centered around the correct treatment strategy in the elderly patient population. The present study investigated whether age predicts the functional outcome of locking plate osteosynthesis for this fracture entity.

METHODS

A consecutive series of patients with surgically treated displaced PHF between 01/2017 and 01/2018 was retrospectively analyzed. Patients were treated by locking plate osteosynthesis. The cohort was divided into two groups: Group 1 (≥65 years) and Group 2 (<65 years). At the follow-up examination, the SSV, CMS, ASES, and Oxford Shoulder Score (OS), as well as a radiological follow-up, was obtained. The quality of fracture reduction is evaluated according to Schnetzke et al. Results: Of the 95 patients, 79 were followed up (83.1%). Group 1 consists of 42 patients (age range: 65-89 years, FU: 25 months) and Group 2 of 37 patients (28-64 years, FU: 24 months). The clinical results showed no significant differences between both groups: SSV 73.4 ± 23.4% (Group 1) vs. 80.5 ± 189% (Group 2). CMS: 79.4 ± 21 vs. 81.9 ± 16, ASES: 77.2 ± 20.4 vs. 77.5 ± 23.1, OS: 39.5 ± 9.1 vs. 40.8 ± 8.2; OS: 39.5 ± 9.1 vs. 40.8 ± 8.2. In the radiological follow-up, fractures healed in all cases. Furthermore, the quality of fracture reduction in both groups is comparable without significant differences. The revision rate was 9.5% in Group 1 vs. 16.2% in Group 2.

DISCUSSION

Both age groups show comparable functional outcomes and complication rates. Thus, the locking plate osteosynthesis can be used irrespective of patient age; the treatment decision should instead be based on fracture morphology and individual patient factors.

Primary stability of cement augmentation in locking plate fixation for proximal humeral fractures: A comparison of absorbable versus non-absorbable cement

BACKGROUND

Cement augmentation has been suggested to increase the stability of screw anchoring in osteoporotic humeral fractures. Initial results are promising but may be jeopardized by cement leakage into the joint and difficult implant removal. Absorbable cement might have advantages in this regard, but it is unclear if the primary stability of both techniques is equivalent to each other. Therefore, this study aimed to compare its primary stability with that of non-absorbable cement augmentation.

METHODS

Nineteen cadaveric humeri with two-part fracture models were treated with locking plate osteosynthesis and cement augmentation using either absorbable calcium phosphate cement (group 1) or polymethylmethacrylate (group 2). Fracture movement, stiffness, failure mode, and ultimate load under cyclic compressive loading were examined and compared between the groups.

FINDINGS

The absolute and relative stiffness values in group 1 were significantly smaller than those in group 2 after 50 cycles (group 1: 114 ± 38 N/mm and 94 ± 8% vs. group 2: 188 ± 71 N/mm and 106 ± 9%; p₅₀ = 0.022), 2000 cycles (group 1: 97 ± 34 N/mm and 81 ± 15% vs. group 2: 153 ± 47 N/mm and 88 ± 15%; p₂₀₀₀ = 0.028), and 5000 cycles (group 1: 98 ± 40 N/mm and 81 ± 22% vs. group 2: 158 ± 40 N/mm and 92 ± 16%; p₅₀₀₀ = 0.028). The failure load was not statistically significantly different between the groups.

INTERPRETATION

Although the PMAA group showed higher values for absolute and relative stiffness, no statistically significant difference was found in the primary stability between absorbable and non-absorbable cement augmentation supporting plate osteosynthesis in proximal humeral fractures. In view of the potential advantages of bio-absorbable cement during the healing process, its use should be considered for the augmentation and stabilization of osteoporotic fractures.

The "Three in One" Bone Repair Strategy for Osteoporotic Fractures

In aging society, osteoporotic fractures have become one major social problem threatening the health of the elderly population in China. Compared with conventional fractures, low bone mass, bone defect and retarded healing issues of osteoporotic fractures lead to great difficulties in treatment and rehabilitation. Addressing major concerns in clinical settings, we proposed the "three in one" bone repair strategy focusing on anti-osteoporosis therapies, appropriate bone grafting and fracture healing accelerating. We summarize misconceptions and repair strategies for osteoporotic fracture management, expecting improvement of prognosis and clinical outcomes for osteoporotic fractures, to further improve therapeutic effect and living quality of patients.

Reconstruction or replacement? A challenging question in surgical treatment of complex humeral head fractures in the elderly

INTRODUCTION

Surgical treatment of complex humeral head fractures in the elderly is challenging due to osteoporotic bone, comorbidities and reduced compliance. The treatment strategy (reconstruction versus replacement) should allow for a functional aftercare and result in a high patient satisfaction. Major complications leading to surgical revision are crucial and should be avoided. The purpose of this study was to analyse the major complication rate leading to surgical revision and the patient-based outcome in complex humeral head fractures of the elderly population treated either using locking plate fixation (LCP) or reversed total shoulder arthroplasty (rTSA).

MATERIALS AND METHODS

All patients older than 65 years surgically treated due to a four-part fracture of the proximal humerus between 2003 and 2015 were enrolled in our retrospective study. Major complications and revision rates were recorded and functional outcome was assessed using the Munich Shoulder Questionnaire (MSQ) allowing for qualitative self-assessment of the Shoulder Pain and Disability Index (SPADI), of the Disability of the Arm, Shoulder and Hand (DASH) score and of the Constant Score.

RESULTS

A cohort of 103 patients with a mean age of 73.4 ± 6.2 years suffering from four-part fractures of the humeral head were enrolled. 63 patients were treated using the LCP fixation compared to 40 rTSAs. There were no significant differences in the patient-reported functional outcome. The revision rate was significantly higher in the LCP group (10/63; 15.9%) compared to the rTSA group (1/40; 2.5%). Reasons for revision were avascular head necrosis, cut-out of screws, secondary dislocation of the greater tuberosity and hypersensitivity to metal.

CONCLUSIONS

Reversed total shoulder arthroplasty and locking plate fixation are both established surgical procedures for the management of complex proximal humerus fractures in the elderly leading to similar functional results. However the revision rate in the rTSA group was significantly lower. Primary rTSA should, therefore, be favoured in multimorbid elderly patients with an increased complication risk to avoid repeated anaesthesia.

Angle-stable polyaxial locked plating with and without polymethylmethacrylate cement augmentation for proximal humeral fractures in elderly

Objectives

This study aims to evaluate the outcomes of proximal humeral fracture (PHF) fixation with a polyaxial locking plate (PLP) osteosynthesis alone versus cement-augmented PLP (PLP-CA) in an elderly population.

Patients and methods

Between May 2015 and June 2018, a total of 101 patients (17 males, 84 females; mean age: 74.5±8.1 years; range, 60 to 94 years) aged ≥60 years with an acute PHF who underwent osteosynthesis with PLP or PLP-CA were retrospectively analyzed. The patients were divided into two groups as the PLP (n=53) and PLP-CA (n=48). Clinical outcomes, Constant-Murley Scores (CMS), Disabilities of the Arm, Shoulder and Hand (DASH) scores, and Short Form-12 (SF-12) scores were compared between the groups.

Results

The overall mean follow-up was 28.1±11.1 months. No clinically relevant differences in the mean duration of surgery, mean intraoperative X-ray image intensifier time or postoperative in-hospital stay were found between the groups. A higher complication rate was observed in the PLP group (20.8% in PLP vs. 10.4% in PLP-CA; p<0.05). There was no statistically significant difference for this (t-test, p=0.08848). The CMS for the operated side did not show any significant differences between the groups. Also, no statically significant difference was seen in the SF-12. A slightly improved DASH score was found for the PLP group (p=0.02908).

Conclusion

During follow-up PLP-CA osteosynthesis yielded nearly similar functional outcomes to PLP fracture fixation, despite with an overall lower rate of complication regarding secondary loss of reduction and screw cut-out. The polymethylmethacrylate cement augmentation can decrease morbidity in this patient group.

Proximal humeral fracture locking plate fixation with anatomic reduction, and a short-and-cemented-screws configuration, dramatically reduces the implant related failure rate in elderly patients

Background

Multiple studies have reported an unacceptable implant-related complication rate in proximal humeral fractures treated with locking plates, particularly in older patients. Our objective was to compare the fracture fixation failure rates in elderly patients, after a dedicated technique for locking plate fixation with cement augmentation or without it.

Methods

A total of 168 open reduction and internal fixation with locking plates were performed for complex proximal humerus fractures by a single surgeon in 136 women and 32 men older than 65 years of age (average 76 years). Treatment groups included group 1 with noncemented screws (n = 90) and group 2 with cemented screws (n = 78). As per Mayo-FJD Classification, there were 74 (44%) varus posteromedial impaction, 41 (24%) algus impaction, 46 (28%) surgical neck, and 7 (4%) head dislocation injuries. A retrospective radiographic and a clinical analysis was performed.

Results

At a mean follow-up of 33 months, the implant failure rate was significantly lower in the cement augmentation group (1% vs. 8%, P = .03). The overall complication rate was 21% (25% group 1, 15% group 2; P = .1). Global avascular necrosis was associated with sustaining a valgus impacted fracture (P = .02 odds ratio 5.7), but not to augmentation. Partial avascular necrosis occurred only in patients treated with cemented screws (3.8%). The overall revision rate was 9% in both groups. Forward elevation was 126 ± 36 degrees and external rotation was 44 ± 19 degrees. The mean Constant score was 70 ± 15 in group 1 and 76 ± 15 in group 2 (P = .03).

Conclusion

Cement augmentation significantly decreased the rate of implant failure. Good results are expected for most patients treated with this technique.

[Individual aspects in eldery patients with fragility fractures]

BACKGROUND

Due to our ageing population, the number of elderly patients who are treated in the emergency department due to low-energy trauma (e.g., tripping) continues to rise. These minor accidents often result in fragility fractures classically located in the proximal humerus, distal radius, spine, pelvis, and near the hip joint. Pre-existing conditions, polypharmacy, and general frailty increase the risk of fragility fractures in this patient population.

METHODS

Geriatric trauma fractures and especially insufficiency fractures of the posterior pelvic ring are often difficult to diagnose by plain X‑ray. Therefore, in geriatric trauma patients, cross-sectional imaging, e.g., computed tomography (CT), dual-energy CT (DECT), or magnetic resonance imaging (MRI), should be considered early for reliable evaluation of a suspected fracture. This also allows for the identification of older fractures. Particularly in cognitively impaired elderly patients, difficult examination conditions or an unclear fall event, cross-sectional imaging is often indicated. However, this may also involve risks, e.g., use of contrast medium in patients with impaired renal function, so that each case must be considered individually. Furthermore, the diagnosis and treatment of osteoporosis, which is an underlying disease that leads to fragility fractures, is of particular importance. In the diagnostic workup, measurement of bone density using dual energy X‑ray absorptiometry (DXA) is the standard method according to guidelines. In specific situations, high-resolution peripheral quantitative CT (HR-pQCT) may also be used.

CONCLUSION

Due to the special challenges of correctly detecting fragility fractures and being able to quickly initiate adequate therapy, good cooperation between radiologists and trauma surgeons is necessary.

DOES CEMENT CURING CAUSE CONCERNING INCREASE OF THE TEMPERATURE WHEN DELIVERED IN THE HUMAN HUMERUS?

For the treatment of humeral fractures, numerous strategies exist to improve the clinical outcome of the reconstruction and to reduce the incidence of fixation failure. Injection of acrylic-based cements to reinforce the bone and/or augment the screws is one option. The heat generated during cement polymerization raises some concerns, as it could cause tissue damage. The first aim of this study was to measure the temperature over time during polymerization when acrylic cements are delivered inside the bone to treat fracture. The second aim was to assess if the ISO-5833:2002 standard can predict what happens in a real bone. Different tests were performed using two acrylic-based cements (Mendec and Cal-Cemex): (i) the ISO-5833:2002 standard (Annex C); (ii) tests on human bones (humeral diaphysis and humeral head) injected with cement to simulate fracture treatment. In the humeri, the highest temperature was measured in the diaphysis (68.6∘C for Mendec, 62.7∘C for Cal-Cemex). These values are comparable with the temperature reached in other consolidated applications (vertebroplasty). Exposure to high temperature was shorter for the diaphysis than for the head. For both cements, in both the diaphysis and the head, temperatures exceeded 48∘C for less than 10[Formula: see text]min. This is within the threshold for tissue necrosis. The ISO-5833:2002 yielded significantly different results in terms of maximum temperature (difference exceeding 15∘C) and exposure to temperature above 48∘C and 45∘C. This discrepancy is probably due to a combination of factors affecting the amount of heat produced and dissipated (e.g., amount and shape of the cement, thermal conductivity).

Promising Mid-Term Outcomes after Humeral Head Preserving Surgery of Posterior Fracture Dislocations of the Proximal Humerus

Background: The aim of this study was to evaluate the clinical outcome after humeral head preserving surgical treatment of posterior fracture dislocations of the proximal humerus. Methods: Patients with a posterior fracture dislocation of the proximal humerus that were operatively treated in two level-1 trauma centers within a timeframe of 8 years were identified. With a minimum follow-up of 2 years, patients with humeral head preserving surgical treatment were invited for examination. Results: 19/24 fractures (79.2%; mean age 43 years) were examined with a mean follow-up of 4.1 ± 2.1 years. Of these, 12 fractures were categorized as posteriorly dislocated impression type fractures, and 7 fractures as posteriorly dislocated surgical neck fractures. Most impression type fractures were treated by open reduction, allo- or autograft impaction and screw fixation (n = 11), while most surgical neck fractures were treated with locked plating (n = 6). Patients with impression type fractures showed significantly better ASES scores (p = 0.041), Simple Shoulder Test scores (p = 0.003), Rowe scores (p = 0.013) and WOSI scores (p = 0.023), when compared to posteriorly dislocated surgical neck fractures. Range of motion was good to excellent for both groups with no significant difference. Conclusions: This mid-term follow-up study reports good to very good clinical results for humeral head preserving treatment.

Double plating - surgical technique and good clinical results in complex and highly unstable proximal humeral fractures

INTRODUCTION

A stable fixation of highly unstable proximal humerus fractures remains challenging and complication rates, especially secondary varus dislocation, remains high. Different techniques of double plate osteosynthesis have been suggested for the treatment of complex proximal humeral fractures as they are well established for other fractures. The aim of this study was to evaluate an operative technique using an angular stable lateral plate supported by a one-third tubular plate positioned anteriorly at the lesser tuberosity for unstable proximal humeral fractures.

PATIENTS AND METHODS

Retrospectively, patients treated with a double plate osteosynthesis were included between January 2014 and December 2017. Out of 31, 25 patients (80.6%) with an average age of 53.1 years ± 12.5 were available for follow-up. 60% of the patients were male. The clinical evaluation consisted of a physical examination and standardised questionnaire including subjective and objective shoulder scores like the Constant-Murley Shoulder Score, Simple Shoulder Score, and Subjective Shoulder Value.

RESULTS

After a mean follow-up of 30.9 months (range, 12-76 months) eighteen patients (72%) had either excellent or good results regarding the Constant-Murley Shoulder Score with a mean value of 77 points ± 17. Average Simple Shoulder Score was 76% ± 0.2 and Subjective Shoulder Value 72% ± 0.2%. Mean NSA at time of follow-up 135° ± 13°. Nine patients had an implant-removal, five in combination with arthrolysis after a mean of 7.2 months. Three patients underwent surgery for secondary arthroplasty. The study shows a complication rate of 16%. No revision-surgery because of secondary varus dislocation was reported.

DISCUSSION

Arthroplasty is the less favourable treatment for a younger, active cohort of patients with highly unstable proximal humeral fractures as results are not as good and options for revision are limited. Double plate osteosynthesis can be used in addition to calcar screws, bone graft augmentation, cement augmentation and additional free screws for more multidirectional stability and shows good clinical results despite a higher rate of avascular necrosis and high primary stability with comparable complication-rates to single plate osteosynthesis. It seems to be a valid alternative to primary fracture arthroplasty and can prevent secondary varus displacement.

Latest Trends in the Current Treatment of Proximal Humeral Fractures - an Analysis of 1162 Cases at a Level-1 Trauma Centre with a Special Focus on Shoulder Surgery

BACKGROUND

The management of proximal humeral fracture (PHF) is not only complex but ever changing. Published epidemiological data are often dated and do not factor in demographic changes or the latest developments in implant material and surgical techniques.

AIMS

The primary aim of this study was to evaluate changes in the epidemiology and actual treatment of PHF at a level-1 trauma centre, with a special focus on shoulder surgery.

HYPOTHESES

1. Between 2009 to 2012 and 2014 to 2017, an increase in complex PHF entities can be observed. 2. In correlation with fracture complexity, an increasing number of comorbidities, especially osteoporosis, can be observed.

METHODS

Between 2014 and 2017, a total of 589 patients (73% female; mean age: 68.96 ± 14.9 years) with 593 PHFs were treated. Patient records and imaging (XRs and CTs) of all patients were analysed. Fractures with ad latus displacement of a maximum of 0,5 cm and/or humeral head angulation of less than 20° were classified as non-displaced. Patients with displaced fractures were included in the analysis of the therapeutic algorithm. These results were compared to those of a cohort 2009 to 2012 (566 patients, 569 PHFs), which used the same inclusion criteria.

RESULTS

The two cohorts showed comparable patient numbers, as well as gender and age distributions. Between 2009 to 2012 and 2014 to 2017, a decrease in 2-part fractures (13.9 to 8.6%) and a simultaneous increase in 4-part fractures (20.4 to 30%), and thus fracture complexity was observed. Further decreases were observed in conservative therapy (27.8 to 20.6%), nail osteosynthesis (10.7 to 2.7%) and anatomic shoulder arthroplasty (5,4 to 1%). Furthermore, there was an increase in the use of locking plate osteosynthesis (43.2 to 56.7%) and reverse shoulder arthroplasty (9 to 18.4%). The general trend shows an increase in surgical therapy between the years (72.2 to 79.4%), as well as an increase in osteoporosis incidence (13 to 20.6%). The greatest numbers of comorbidities were found in 3- and 4-part fractures.

CONCLUSION

There is an increase in both the complexity of fractures and the number of surgically treated fractures between 2009 and 2012. Furthermore, an increase in osteoporosis numbers can be observed. New implants (PEEK, fenestrated screws for cement augmentation) and new surgical techniques (double plating osteosynthesis) were used as a result of increasing fracture complexity. Moreover, reverse total shoulder arthroplasty was used more commonly.

Reconstruction of proximal humeral fractures without screws using a reinforced bone substitute

Multi-fragment fractures are still a challenge: current clinical practice relies on plates and screws. Treatment of fractures of the proximal humerus has the intra-operative risk of articular damage when inserting multiple screws. Distal-varus collapse of the head is a frequent complication in osteoporotic patients. The aim of this biomechanical study was to investigate if an Innovative-cement-technique (the screws are replaced by injection of cement) provides the same or better stability of the reconstructed head compared to the Standard-technique (locking screws). A four-fragment fracture was simulated in twelve pairs of humeri, with removal of part of the cancellous bone to simulate osteoporotic "eggshell" defect. One humerus of each pair was repaired either with a Standard-technique (locking plate, 2 cortical and 6 locking screws), or with the Innovative-cement-technique (injection of a partially-resorbable reinforced bone substitute consisting of PMMA additivated with 26% beta-TCP). Cement injection was performed both in the lab and under fluoroscopic monitoring. The reconstructed specimens were tested to failure with a cyclic force of increasing amplitude. The Innovative-cement-technique withstood a force 3.57 times larger than the contralateral Standard reconstructions before failure started. The maximum force before final collapse for the Innovative-cement-technique was 3.56 times larger than the contralateral Standard-technique. These differences were statistically significant. The Innovative-cement-technique, based on the reinforced bone substitute, demonstrated better biomechanical properties compared to the Standard-technique. These findings, along with the advantage of avoiding the possible complications associated with the locking screws, may help safer and more effective treatment in case of osteoporotic multi-fragment humeral fractures.

Cement augmentation of calcar screws may provide the greatest reduction in predicted screw cut-out risk for proximal humerus plating based on validated parametric computational modelling: Augmenting proximal humerus fracture plating

Aims

Fixation of osteoporotic proximal humerus fractures remains challenging even with state-of-the-art locking plates. Despite the demonstrated biomechanical benefit of screw tip augmentation with bone cement, the clinical findings have remained unclear, potentially as the optimal augmentation combinations are unknown. The aim of this study was to systematically evaluate the biomechanical benefits of the augmentation options in a humeral locking plate using finite element analysis (FEA).

Methods

A total of 64 cement augmentation configurations were analyzed using six screws of a locking plate to virtually fix unstable three-part fractures in 24 low-density proximal humerus models under three physiological loading cases (4,608 simulations). The biomechanical benefit of augmentation was evaluated through an established FEA methodology using the average peri-screw bone strain as a validated predictor of cyclic cut-out failure.

Results

The biomechanical benefit was already significant with a single cemented screw and increased with the number of augmented screws, but the configuration was highly influential. The best two-screw (mean 23%, SD 3% reduction) and the worst four-screw (mean 22%, SD 5%) combinations performed similarly. The largest benefits were achieved with augmenting screws purchasing into the calcar and having posteriorly located tips. Local bone mineral density was not directly related to the improvement.

Conclusion

The number and configuration of cemented screws strongly determined how augmentation can alleviate the predicted risk of cut-out failure. Screws purchasing in the calcar and posterior humeral head regions may be prioritized. Although requiring clinical corroborations, these findings may explain the controversial results of previous clinical studies not controlling the choices of screw augmentation.

Complication rate after operative treatment of three- and four-part fractures of the proximal humerus: locking plate osteosynthesis versus proximal humeral nail

PURPOSE

There is still disagreement regarding the optimal surgical treatment of three- and four-part fractures of the proximal humerus. The aim of this monocentric, retrospective study was to compare the complication rate of internal fixation with a locking plate versus proximal humeral nailing after a one-year follow-up.

METHODS

From 2005 to 2016, 292 patients suffered a fracture of the proximal humerus and were treated surgically at our level-I trauma center. According to the inclusion criteria, 50 patients were included in this study: 19 of these (11 three-part fractures and 8 four-part fractures) were treated with a proximal humeral nail (HN) and 31 (12 three-part fractures and 19 four-part fractures) with a locking plate (LP) osteosynthesis. Classification was performed according to the Hertel classification. At a 1-year follow-up, the complication rate of the two treatment methods was compared.

RESULTS

Twenty patients (40%) suffered at least one complication. Of these, six patients (12%) were treated with a HN and 14 (28%) with a LP (p = 0.39). The most frequent complication was screw perforation (22%), followed by non-union (16%). Humeral head necrosis (10%) occurred only in the LP cohort. One wound infection occurred in a patient treated with a HN. Four-part fractures were treated more frequently with a LP. However, the difference was non-significant in this sample (p = 0.186).

CONCLUSIONS

The results of our study provide some evidence that in terms of complication rate, both treatment options are comparable for internal fixation of three- and four-part fractures of the proximal humerus. The type of fracture seems to be decisive for the choice of implant.

Synthetic Bone Substitutes and Mechanical Devices for the Augmentation of Osteoporotic Proximal Humeral Fractures: A Systematic Review of Clinical Studies

BACKGROUND

Different augmentation techniques have been described in the literature in addition to the surgical treatment of proximal humeral fractures. The aim of this systematic review was to analyze the use of cements, bone substitutes, and other devices for the augmentation of proximal humeral fractures.

METHODS

A systematic review was conducted by using PubMed/MEDLINE, ISI Web of Knowledge, Cochrane Library, Scopus/EMBASE, and Google Scholar databases according the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines over the years 1966 to 2019. The search term "humeral fracture proximal" was combined with "augmentation"; "polymethylmethacrylate, PMMA"; "cement"; "bone substitutes"; "hydroxyapatite"; "calcium phosphates"; "calcium sulfate"; "cell therapies", and "tissue engineering" to find the literature relevant to the topic under review.

RESULTS

A total of 10 clinical studies considered eligible for the review, with a total of 308 patients, were included. Mean age at the time of injury was 68.8 years (range of 58-92). The most commonly described techniques were reinforcing the screw-bone interface with bone PMMA cement (three studies), filling the metaphyseal void with synthetic bone substitutes (five studies), and enhancing structural support with metallic devices (two studies).

CONCLUSION

PMMA cementation could improve screw-tip fixation. Calcium phosphate and calcium sulfate injectable composites provided good biocompatibility, osteoconductivity, and lower mechanical failure rate when compared to non-augmented fractures. Mechanical devices currently have a limited role. However, the available evidence is provided mainly by level III to IV studies, and none of the proposed techniques have been sufficiently studied.

Mechanical Effects of Bone Substitute and Far-Cortical Locking Techniques in 2-Part Proximal Humerus Fracture Reconstruction: A Cadaveric Study

OBJECTIVES

To make direct comparisons of the biomechanical properties of a control (CTL) group and implants that were augmented with far cortical locking (FCL), bone substitute material (BSM), and a combination of both (ALL) to determine which fixation is most effective in reducing implant failure.

METHODS

The constructs were tested with osteopenic cadaveric specimens in a two-part fracture model. Specimens were subjected to a battery of nondestructive torsion and axial compression tests, followed by a cyclic test. Construct stiffness and cycles to failure were documented, pre- and post-test fluoroscopy was performed, and implant and bone kinematics were quantified.

RESULTS

During nondestructive testing, the BSM group exhibited significantly increased torsional and axial stiffness compared with the FCL (P = 0.006, P < 0.001) group and ALL group (P < 0.001, P = 0.006). There were no significant differences in resistance to cyclic loading between groups. Fluoroscopic analysis indicated significant differences in the motions of nonlocked cannulated screws (used in BSM and ALL) versus locked screws (used in CTL and FCL).

CONCLUSIONS

Patients with poor bone quality and proximal humerus fracture may necessitate added compliance or rigidity to achieve fixation. Both have exhibited favorable biomechanical characteristics in this cadaveric 2-part proximal humerus fracture model.

Does cement augmentation of the screws in angular stable plating for proximal humerus fractures influence the radiological outcome: a retrospective assessment

BACKGROUND

Screw-tip augmentation in angular stable plating offers new possibilities for the treatment of complex proximal humerus fractures. This retrospective analysis was performed to evaluate the radiological outcome of proximal humerus fractures treated with angular stable plates and additional screw-tip cement augmentation in patients over the age of 60.

MATERIALS AND METHODS

A retrospective single centre analysis was conducted from June 2013 to December 2016. The minimum follow-up time was set to 6 months after surgery. Anatomical reduction and fixation were evaluated in respect to reattached tuberosities to the head fragment and the adequate restoration of the calcar area not showing any valgus or varus malalignment. Complete fracture healing was determined 3 months after surgery. Any failures such as secondary displacement, primary screw perforation, intraarticular cement leakage and avascular necrosis of the humeral head with concomitant screw cut-out were assessed.

RESULTS

In total, 24 patients (21 females; 3 males) at a median age of 77.5 (62-96) years were included. Five 2-part, twelve 3-part and seven 4-part fractures were detected. The measured median BMD value of 23 patients was 78.4 mg/cm³ (38.8-136.9 mg/cm³). Anatomical reduction was achieved in 50% of the patients. In most cases, the A level screws and the B1 screw were augmented with bone cement by a median of 7 (5-9) head screws used. Postoperative varus displacement was not detected in any of the patients. One patient (4.2%) sustained an early secondary displacement. Intraarticular cement leakage was detected in 3 patients (2 head-split fractures). Avascular necrosis of the humeral head was observed in 4 patients (16.7%). Revision surgery was necessary in four cases, using hemiarthroplasty twice and reverse shoulder arthroplasty the other two times.

CONCLUSION

Screw-tip augmentation in angular stable plating for proximal humerus fracture treatment showed a low secondary displacement rate of 4.2% in patients suffering from poor bone quality. Nevertheless, the occurrence of avascular necrosis of the humeral head with mainly severe fracture patterns observed in this study was higher compared to previously reported results in the literature. Cement augmentation in head-split fractures is not recommended, considering the high risk of an intraarticular cement leakage.

Osteoporotic Bone: When and How to Use Augmentation?

The number of fragility fractures is rising, and treatment is a challenge for orthopaedic trauma surgeons. Various augmentation options have been developed to prevent mechanical failure. Different composites can be used based on the fracture type, patient needs, and biomechanical needs. Indications for augmentation are not limited to osteoporotic fractures but can also be performed as a salvage procedure or in pathologic fractures. Biomechanical studies have shown advantages for augmented implants in the spine, proximal femur, and humerus. Clinical studies are preliminary but promising, showing good clinical results after augmentation with reduced mechanical failure and minimal complications.

Augmentation of plate osteosynthesis for proximal humeral fractures: a systematic review of current biomechanical and clinical studies

INTRODUCTION

Secondary dislocation due to loss of fixation is the most common complication after plate fixation of proximal humeral fractures. A wide range of different techniques for augmentation has been described to improve the primary and secondary stability. Nevertheless, comparative analyses on the specific advantages and limitations are missing. Therefore, the aim of the present article was to systematically review and evaluate the current biomechanical and clinical studies.

MATERIALS AND METHODS

The databases of PubMed and EMBASE were comprehensively searched for studies on augmentation techniques for proximal humeral fractures using defined search terms. Subsequently, all articles identified were screened for eligibility and subdivided in either clinical or biomechanical studies. Furthermore, the level of evidence and study quality were assessed according the Oxford Centre for Evidence-Based Medicine and the Coleman Methodology Score, respectively.

RESULTS

Out of 2788, 15 biomechanical and 30 clinical studies were included. The most common techniques were structural allogenic or autologous bone grafting to enhance the medial support, metaphyseal void filling utilizing synthetic bone substitutes or bone grafts, and screw-tip augmentation with bone cement. Biomechanical data were available for structural bone grafting to enhance the medial support, void filling with synthetic bone substitutes, as well as for screw-tip augmentation. Clinical evidence ranged from level II-IV and study quality was 26-70/100 points. Only one clinical study was found investigating screw-tip augmentation. All studies included revealed that any kind of augmentation positively enhances mechanical stability, reduces the rate of secondary dislocation, and improves patients' clinical outcome. None of the studies showed relevant augmentation-associated complication rates.

CONCLUSIONS

Augmentation of plate fixation for proximal humeral fractures seems to be a reliable and safe procedure. All common techniques mechanically increase the constructs' stability. Clinically evaluated procedures show reduced complication rates and improved patient outcomes. Augmentation techniques seem to have the highest significance in situations of reduced bone mineral density and in high-risk fractures, such as 4-part fractures. However, more high-quality and comparative clinical trials are needed to give evidence-based treatment recommendations.

Cement augmentation of the proximal humerus internal locking system in elderly patients: a multicenter randomized controlled trial

INTRODUCTION

Cement augmentation of the proximal humerus internal locking system (PHILOS) screws might reduce complication rates in osteoporotic bones. This study compared the risk of mechanical failure during the first year after PHILOS™ treatment of proximal humerus fractures (PHF) without (control group) and with (augmented group) screw augmentation. Secondary objectives were to report shoulder functions, quality of life (QoL), adverse events (AEs), and reoperation rates.

MATERIALS AND METHODS

This multicenter randomized trial enrolled patients aged ≥ 65 years with displaced/unstable PHF from eight European centers. Randomization was performed during surgery through sealed opaque envelopes. Mechanical failures were assessed by two independent reviewers via radiographs, shoulder function by Quick DASH, SPADI, and Constant Murley scores, and QoL by EQ-5D. Follow-ups were planned at postoperative 6 weeks, 3, 6, and 12 months.

RESULTS

The preliminary analysis of 6-week radiographs of the first 59 enrolled patients suggested a mechanical failure rate lower than expected and the difference between groups was too small to be detected by the planned sample size of 144. The trial was prematurely terminated after 67 patients had been enrolled: 34 (27 eligible) in the control group and 33 (29 eligible) in the augmented group. Follow-ups were performed as planned. Nine patients had mechanical failures and the failure rates (95% CI) were: augmented group, 16.1% (5.5; 33.7); control group, 14.8% (4.2; 33.7); the relative risk (95% CI) for the augmented group was 1.09 (0.32; 3.65) compared to the control group (p = 1.000). No statistically significant differences in shoulder function, QoL, and AEs were observed between study groups at 1 year. Nine patients (15.8%) underwent a revision.

CONCLUSIONS

Due to premature termination, the study was underpowered. A larger study will be necessary to determine if cement augmentation lowers the risk of mechanical failure rate.